Creating A Self Sustaining Environment?

[highlandjunkie]

does anyone have any ideas on creating a self sustaining environment? All I want to put in is a heater the rest I want to be all natural. I was thinking something like a cory or 2, a betta, a snail, and some plants. so heres what I need - live reproducing freshwater food - fish and snails that get along - Good plants to put in the tank The size of my tank can be as big 63l or 16 gallons. Thanks a bunch RR :D

[Callatya]

How long do you want it to self-sustain for? In reality, in order to create a self-sustaining environment you'd need a massive massive wetland. In a home tank, you can't easily replicate the denitrifying bacteria (the stuff that breaks down nitrate and requires anaerobic conditions) so the goal of fully self-sustaining is pretty much out of reach. You can get as close as possible, but you'll stil have to provide "rain" and "flood" and some sort of current unless you are trying to replicate a wetland area that would just use the frequent rain to flush the water through. You'll also have to play predator occasionally and yank out a few fish and plants, and add the odd thing (bird poo might be a bit too real, but maybe some water bugs or worms) Try to find a book by Debbie Walstead (? i think) who does fantastic tanks using a soil and gravel substrate. That should (if you can get the right soil) save you using ferts. I'd suggest some stem plants like elodea and vallis, and maybe some java moss. If you can't rplicate sunlight, you might want to bypass the live plants as they'll cause more problems than not. If this is the case, go with a rocky biotope with no plants or super dooper low light plants that will survive on room light. I'd skip the cory (they need good water conditions and this is a very ambitious project that will probably take several months to get stable, so i'd leave the cory. they do much better in schools anyway, and a 16 gal with no filter couldn't support it IMO. I'd stay with snails for bottom feeders, or 3-4 kuhlies as they are smaller and real garbage gutses! Have you thought about a few female bettas or wild bettas? they'd be your best bet in unfiltered water and cope well providing you deposited enough food. You'll have to be a bit generous until you find a method that will give you good live food in-tank, i'd say maybe farm-bred tubifex or blackworms and ramshorns for emergencies, depending on your substrate. Its a great idea, and one that has been tried with varying degrees of success before. The thing is that in order to be natural, you have to include EVERYTHING that would naturally happen within that environment and mimick it as best as possible. Sometimes that does mean having more gizmos and equiptment and interfering a bit more than planned, but there is only so natural you can be with a small glass box If the goal is low maintenence, very little power and looking natural, thats much easier God luck!

[highlandjunkie]

thank you vary much! It's actully a school project and I had to choose this or breeding corys and I thought this would be lots of fun. any how I will keep you posted. Oh! and should my tank be long and skinny or fat and tall? RR

[Mishy]

Go for width over height. A bigger bottom means that the tank's weight is spread over a bigger area which equals less chance of the tank breaking due to stress.

[VickiPS]

Abbey's given you lots of good advice. My only suggestion would be to perhaps think about either native fish species or else fish that do well in planted ponds (ie. where there is closer to a self-sustaining environment). For example, pacific blue-eyes, swords, WCM minnows, small gudgeons, even a goldfish might be worth considering.

[Callatya]

Ahh, OK. For a school project it only has to self-sustain for a little while. If they want a fully closed system (no adding of water, no evaporation etc) then I think you can keep it going for a little while, maybe 2 weeks or so. On the offchance the project is anythng like the US style closed system in a soda bottle, make sure you don't make the tank airtight. At the very least there needs to be some gas exchange in order for the plants and animals to breathe. There just isn't enough room in a tank that size to have good gas exchange while being fully sealed. If you think about up and down, and how many kilometers down the earth is fertile and able to support life (not many), and thn how many kilometers up there is to keep that fuctioning(lots and lots), it just isn't able to be replicated in a tank. It sounds like your teachers have a much better idea than the "guppy and duckweed in a soda bottle for a month" system, but just in case it is suggested, make sure that you don't seal it totally. If they want to make it tamper-proof, I'm sure we can come up with something :(

[highlandjunkie]

thanks soo much I think I'm gonna take the suggestions and go with the flow.